Experimental Investigation of the Flow Structure Near a Single Wraparound Fin
Additional Document Info
1996 by Lockheed Martin Corporation. All rights reserved. A wall-mounted semi-cylindrical model containing a single wrap-around fin (WAF) was tested in the AFIT Mach 2.9 test facility. Detailed mean flow and turbulence measurements were obtained using conventional probes and cross-wire hot-film anemometry at a series of stations upstream of and aft of the fin leading edge. Results showed the turbulence intensity in the fuselage boundary layer to be far greater on the concave side of the fin than on the convex side. In fact, at the location that boundary layer measurements were taken (0.69c), the turbulence intensities actually decreased by up to 70% when compared to pre-interaction values on the convex side of the fin - and increased by as much as 50% on the concave side. Similarly, the Reynolds shear stress aft of the fin bow shock is reduced on the convex side of the fin and rises dramatically on the concave side. These results qualitatively agree with the observed stabilizing and destabilizing effects of pressure gradient distortion on supersonic boundary layers.